<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <script src="../vue.global.js"></script>
  </head>
  <body>
    <div id="counter">Counter: {{ counter }}</div>
    <script>
      //   const Counter = {
      //     data() {
      //       return {
      //         counter: 123,
      //       };
      //     },
      //   };

      const Counter = {
        data() {
          return {
            counter: 0,
          };
        },

        /* Counter组件【挂载完毕】时回调mounted【生命周期】 */
        mounted() {
          setInterval(() => {
            this.counter++;
          }, 1000);
        },
      };

      Vue.createApp(Counter).mount("#counter");
    </script>
  </body>
</html>
